Fast image enlargement using predefined codebook and eigenspace backprojection for lost pixel

In this paper, a new image enlargement method applying the backprojection for lost pixel (BPLP) to the predefined codebook-based method is proposed. BPLP is a method for image restoration. In BPLP, the eigenspace reflecting the characteristics of an input image is generated from the remained pixels and is used to restore the missing pixels. In the proposed method, the eigenspace is replaced by one generated from the predefined codebook (PDC). PDC represents edge-blurring properties in a small image patch and consists of pairs of low- and high-frequency image patches on various edge patterns. By replacing the PDC-based estimation of lost high-frequency components with BPLP, a fast image enlargement method retaining its performance can be developed. Through some experiments, the effectiveness of the proposed method was demonstrated. Especially, it was confirmed that the processing time of the proposed method was shortened to about 1/50 that of the PDC-based method.     

Elliptical Solutions to the Standard Cosmology Model with Realistic Values of Matter Density

We have examined a solution to the FRW model of the Einstein and de Sitter Universe, often termed the standard model of cosmology, using wide values for the normalized cosmic constant (Ω_∧) and spacetime curvature (Ω _k ) with proposed values of normalized matter density. These solutions were evaluated using a combination of the third type of elliptical equations and were found to display critical points for redshift z, between 1 and 3, when Ω_∧ is positive. These critical points occur at values for normalized cosmic constant higher than those currently thought important, though we find this solution interesting because the Ω_∧ term may increase in dominance as the Universe evolves bringing this discontinuity into importance. We also find positive Ω_∧tends towards attractive at values of z which are commonly observed for distant galaxies.     

Polarity determination of wurtzite-type crystals using hard x-ray photoelectron diffraction

The surface structure of a single-crystal ZnO wafer was studied by angle-resolved x-ray photoelectron spectroscopy (ARXPS) using synchrotron radiation. As a result, well-defined x-ray photoelectron diffraction (XPD) patterns were obtained for the (0001) and (000$\overline{1}$) polar surfaces using the photoemission from the Zn 2p_3/2 and O 1s core levels. The XPD patterns were indexed assuming forward scattering of photoelectrons by neighboring ions. Further, the XPD patterns for the (0001) and (000$\overline{1}$) surfaces were different from each other, indicating the possibility for using the XPD technique for polarity determination.     

Equivalence Groups for First-Order Balance Equations and Applications to Electromagnetism

We investigate the groups of equivalence transformations for first-order balance equations involving an arbitrary number of dependent and independent variables. We obtain the determining equations and find their explicit solutions. The approach to this problem is based on a geometric method that depends on Cartan's exterior differential forms. The general solutions of the determining equations for equivalence transformations for first-order systems are applied to a class of the Maxwell equations of electrodynamics.     

On input/output stabilization of singular integrodifferential systems

In this paper we consider a class of systems described by singular integrodifferential equations. This type of systems appear, for example, in the modeling of certain aeroelastic control problems. We study these systems in frequency domain framework and show the existence of finite-dimensional stabilizing controllers. An algorithmic procedure is outlined for the construction of such controllers. In order to illustrate the numerical aspects of this algorithm, we present an example involving the classical Theodorsen model of an airfoil, which fits in the class of systems considered here.This work was supported in part by the National Science Foundation under Grants DMS-8907019 and MSS-9203418.     

Exact traveling wave solutions of perturbed nonlinear Schrödinger's equation (NLSE) with Kerr law nonlinearity

By using new solutions of nonlinear partial differential equation, a direct algebraic method is described to construct the exact traveling wave solutions for perturbed nonlinear Schrödinger's equation (NLSE). Exact traveling wave solutions are explicitly obtained by this method.     

Study of phase transition in a [CdHgI4 : 0.2AgI] mixed conducting composite system doped with KI and K2SO4

New composite superionic systems, [CdHgI₄?:?0.2AgI]?:?0.xKI and [CdHgI₄?:?0.2AgI]?:?0.xK₂SO₄ (x?=?0.2, 0.4, 0.6?mol. wt%), were prepared, using [CdHgI₄?:?0.2AgI] mixed composite system as the host. Electrical conductivity was measured to study the transition behavior at frequencies of 100?Hz, 120?Hz, 1?kHz, and 10?kHz in the temperature range from 150°C to 250°C using a GENRAD 1659 RLC Digibridge. A sharp increase in conductivity was observed during β?→?α phase transition. Upon increasing the dopant-to-host ratio, the conductivity of the superionic systems exhibited Arrhenius (thermally activated)-type behavior. Differential thermal analysis, differential scanning calorimetry, thermogravimetric analysis, and X-ray powder diffraction were performed to confirm the doping effect and transition in the host. The phase transition temperature increased with an increase in the dopant concentration. Activation energies in eV for pre- and post-transition phase behavior are reported.